V1 is a PCL – but V2 now targets netstandard 1.3 (and classic .NET 4.5). Since we have quite a big user base for V1, we didn’t want to break anyone doing that change. This is the reason why v1 and v2 now live in separate repos and can evolve independently if needed.

See the readme for examples what IdentityModel can do – and – as always give us feedback via the issue tracker.